A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Prismatic Geometric Pattern Background No Black
Source GDJ
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
Colour version of the original seamless pattern.
Source Firkin
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee